1. Field of the Invention
The present invention relates to a wireless network, i.e., for automation, realtime and/or industrial applications, having at least two access network nodes and at least one radio station for wirelessly communicating with at least one of the at least two access network nodes, where each of the at least two access network nodes uses a data channel selected from a set of available selectable data channels for wireless communication with a radio station assigned to each access network node.
2. Description of the Related Art
In general, wireless networks are known. For example, US Publication No. 2006/0221993 A1 discloses a wireless local area network (WLAN) having a plurality of access network nodes, i.e., “access points”, and a multiplicity of radio stations in the radio coverage area of the access points. In this arrangement, an access point selects, from a plurality of available frequencies, a free frequency on which the access point communicates with the radio stations located within its radio coverage area. In this case, each access point sends a polling message at regular intervals to all of its radio stations, where the message affords the receiving station the opportunity to send data back to the access point. In order to avoid mutual interference among the different access points in the network, the different access points communicate with their respective radio stations on different WLAN channels that are assigned to different frequencies.
It is a shortcoming of the conventional networks that a radio station looking for the best possible access point for communication must search through different radio frequencies for corresponding signals or messages. This is disadvantageous in cases of realtime communication protocols, because this search step on a plurality of frequencies is relatively time-consuming and during this time the radio station is unable to conduct any normal data communication and as a consequence possibly cannot comply with response times prescribed in the realtime communication protocol.